<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div>
        <input type='file' name='file' onchange='uploadFile(this);'/>
    </div>
    <div>
        <pre id='ret-content'></pre>
    </div>
</body>
<script>
    function uploadFile(t){
if(t.files.length<=0)return;
let fm=new FormData();
fm.append('file',t.files[0]);
fetch('/upload',{
    method:'POST',
    body:fm
})
.then(async res=>{
    if(res.ok){
        return res.text();
    }
    throw new Error(`${res.status} ${res.statusText}`)
})
.then(text=>{
    let d=document.getElementById('ret-content');
    d.innerHTML=`<img src="/images/${text}" style="width:80%;height:auto;">`;
})
.catch(err=>{
    console.error(err.message);
})
    }
</script>
</html>